Fluid filter with an attachment structure on an endplate of the filtering element

ABSTRACT

A fluid filter includes a filter element having a filtering media disposed between two endplates. One endplate includes an open flow passage that allows a working fluid to flow into or out of the media during operation. The other endplate includes a connection structure. A cover houses the filter element, and has an opening that is an inlet or outlet in fluid communication with the opening of the one endplate. The cover includes another fill opening proximate the other endplate. A cap is connected to the connection structure of the other endplate to close the opening of the cover. The cover is retained between the cap and other endplate. Generally, the attachment configuration between the cap and the other endplate of the filter element helps ensure that the filter element with the correct micron rating is installed in a filtration system.

FIELD

The present disclosure relates generally to fluid filters and theirassemblies. More particularly, the present disclosure relates to animproved attachment interface of a filter where its filter element isdirectly connected to a cap, and retains the fluid filter shell. Such adesign can help ensure use of a filter element with the proper micronrating.

BACKGROUND

Fluid filters are widely known and used in various systems andapplications, for example such systems that require particle and/orfluid separation from a working fluid. As one examples fuel filtrationsystems for engines are well known and employ fluid filters thatoftentimes have fuel filtration capabilities based on different micronratings. Generally, a micron rating for a fluid filter is one way ofindicating the ability of the filter's media to remove contaminants bythe size of particles it is exposed to. As some examples, fluid filterscan have micron rated filter elements ranging from 3 to 50 micron.

Installing the proper micron rated filter element into a fluid filter isimportant for maintaining efficient filtration in a given filtrationsystem and for protecting equipment, such as an engine. With fuelfilters, for example, their filter elements often look similar andinadvertent installation of the wrong micron rated filter element canoccur. For example, such an accident can easily occur during servicingand maintenance in the aftermarket. It is desired that such accidents beprevented or at least minimized.

Improvements can be made upon existing fluid filter designs.Particularly, structural improvements can be made as to how a fluidfilter is assembled and to help control that the correct micron ratedfilter element is installed.

SUMMARY

The present disclosure generally relates to a fluid filter that includesa unique attachment interface for its assembly. Generally, the uniqueattachment interface includes a filter element with an endplate that isdirectly connected to a cap that can be opened and closed for filling.The endplate structure described herein cart also provide a controlfeature helpful to insure that the correct filter element is beingassembled into the fluid filter and can help make installation easier.

In one embodiment, a fluid filter includes a filter element having amedia disposed between two endplates. The media allows a working fluidto be filtered through the media. One of the two endplates includes anopen flow passage that allows the working fluid to flow into or out ofthe filter media during operation. The other of the two endplatesincludes a connection structure. A cover houses the filter element. Thecover has an opening in fluid communication with the flow passage of theone endplate and has a fill opening proximate the other of the twoendplates. A cap closes the cover at the opening proximate the other ofthe two endplates. The cap is connected to the connection structure ofthe other of the two endplates, such that the cover is retained thereby.

The endplate can be configured and arranged to control which filterelement can be used in the fluid filter assembly. In some embodiments,the connection structure of the other of the two endplates correspondsto a micron rating of the media of the filter element, and controlswhich filter element can be used in the fluid filter assembly. As oneexample, the connection structure is a threaded arrangement.

In other embodiments, the other of the two endplates includes at leastone slot on an outer surface thereof. In some examples, the at least oneslot is configured to correspond to a micron rating of the media of thefilter element.

In yet another embodiment, the other of the two endplates includes aplurality of tabs disposed about a perimeter thereof. The tabs extendoutward from the perimeter. In some examples, the tabs are configured tocorrespond to a micron rating of the media.

In another embodiment, a method for assembling, a fluid filter assemblyincludes placing a filter element within a cover that generally housesthe filter element. A cap is inserted through an opening of the cover.The cap is directly connected to an endplate of the filter element.Through the direct connection of the cap and endplate, the cover isretained by the cap and filter element.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a fluid filter.

FIG. 2 is a sectional view of the fluid filter of FIG. 1 and showing oneembodiment of a filter element having its endplate directly connected toa cap.

FIG. 3 is a perspective view of the endplate shown alone.

FIG. 4 is a top perspective view of the filter element of FIG. 1 alone.

FIG. 5 is a bottom perspective view of the filter element of FIG. 1alone.

FIG. 6 is a top view of the fluid filter of FIG. 1.

FIG. 7 is a partially exploded view of the fluid filter of FIG. 1.

FIG. 8 is a top sectional view of the fluid filter of FIG. 1.

FIG. 9 is an exploded view of another embodiment of a fluid filter.

FIG. 10 is sectional view of the fluid filter of FIG. 9.

FIG. 11 is a partial sectional view of the fluid filter of FIG. 9 takenfrom the top.

DETAILED DESCRIPTION

FIGS. 1-11 of the present disclosure generally relate to a fluid filterthat includes a unique attachment interface for its assembly, where afilter element is directly connected to a cap that can be opened andclosed for filling. The endplate structure described herein can providea control feature helpful to insure that the correct filter element isbeing assembled into the fluid filter and can help make installationeasier. The descriptions herein can also provide a filter element thatprotects aftermarket considerations, as the correct filter element isneeded for installation/servicing.

FIGS. 1-8 show one example of a fluid filter 10. In one embodiment, thefluid filter 10 is employed as a fuel filter. Fuel filters and theiruses are well known. For illustration purposes only, the inventiveconcepts for a filter design are described with respect to a fuelfilter. It will be appreciated, however, that the disclosure is notmeant to be limiting to fuel filters, and that the inventive conceptsdescribed herein can be used in and suitably adapted for other fluidfilter assemblies, such as by-pass and lube filtration technologies. Itwill be further appreciated that various working fluids in need offiltration, including but not limited to fuel, can benefit from theinventive concepts disclosed herein.

FIGS. 1-8 show an improved attachment interface or configuration thatcan be used in such fuel filtration systems. The fluid filter 10 is anassembly generally including a cover 12, a filter element 11, and a cap16.

The filter element 11 resembles a cartridge-like structure having afiltering media 14 disposed between two endplates 20, 22. Generally, themedia 14 allows a working fluid to be filtered therethrough. It will beappreciated that material for filtration media and their constructionsare well known. It further will be appreciated that the filtering media14 can have various micron ratings to achieve a desired filtrationcapability for removing undesired contaminants of various sizes from theworking fluid. As some examples only, the filtering media 14 can beconstructed of material so as to give the filtering media a micronrating in the range of 3 to 50 microns. Installing the proper micronrated filter element into a fluid filter is important for maintainingefficient filtration in a given filtration system and for protectingoperating equipment, such as an engine. As one example shown in FIG. 1,the media 14 is a pleated material that can have a wrap 14 a. It will beappreciated that the pleated construction and the wrap are just oneexample of a construction for the media 14 and are not meant to belimiting.

In one embodiment, endplate 22 is a bottom endplate and includes an openflow passage 52 (best shown in FIG. 5) that allows a working fluid toflow into or out of the filtering media 14 during operation. The flowpassage 52 is for connecting the fluid filter 10 to other equipment of afiltration system. In one embodiments endplate 20 is a top endplate. Itwill be appreciated that either endplate 20, 22 may be configured tohave the flow passage 52, and that the reference to top and bottom isfor illustration purposes. The orientation of the filter element 11 withrespect to its positioning in the cover 12 is dependent upon which ofthe endplates 20, 22 has the flow passage 52.

In some examples, the endplate that does not have the flow passage (e.g.endplate 20) is a closed structure. That is, the endplate 20 does nothave any openings and closes off one end of the filter media. In otherexamples, the endplate 20 can have a valve 18 disposed at an opening 38thereof. When such a valve 18 is employed, it can close over time duringoperation, for example when the filter element 11 needs to be replaced,such as when the fluid filter 10 is filled with ‘dirty’ fluid during itsparticular filtration application (e.g. fuel filtration). As oneexample, the valve 18 is a check valve or cracking pressure valve asgenerally known by one of skill in the art. In FIG. 2, the valve 18 is aone-way seated member or plunger-like structure that can close theopening in the endplate 20.

The cover 12 generally houses the filter element 11. The cover 12 has anopening that is in fluid communication with the flow passage 52 of theendplate 22. As shown in FIG. 1, the cover 12 may be a clear orgenerally transparent cover that one can see through. The cover 12 isgenerally open on a side or end that is in fluid communication with theflow passage 52 (see bottom of fluid filter 10). The cover 12 alsoincludes an opening 13 proximate the endplate 20. As shown, the cover 12has wall surfaces that surround the opening 13. These wall surfaces areretained between the connection of the cap 16 to the endplate 20 whenthe fluid filter 10 is assembled (further described below).

The cap 16 closes the opening 13 of the cover 12. A seal 42 can bedisposed about the opening 13 or on the cap 16. In one embodiment, theseal 42 is an o-ring. In the closed position, the cap 16 is directlyconnected to the endplate 20.

The endplate 20 includes a connection structure 30. The cap 16 isconnected to the connection structure 30 of the endplate 20, such thatthe cover 12 is retained between the cap 16 and the endplate 20 (seee.g. FIG. 2).

In one embodiment, the connection structure 30 of the endplate includesa threaded arrangement. As shown, the connection structure 30 is athreaded portion that can be threadedly engaged with a threaded portion40 on the cap 16. As one example, the connection structure 30 isconstructed as a raised boss structure extending from a main surface ofthe endplate 20 and having a female threaded portion, and the cap 16 isconstructed as a male threaded portion.

It will be appreciated that other threaded arrangements may be employed,for example, the endplate 20 may have the male thread and the cap mayhave the female thread. It further will be appreciated that theconnection structure 30 of the endplate 20 is not meant to be limitingto a threaded arrangement. Other examples that can be used include butare not limited to a snap fit, an interference fit, or a quarter turnlock, or other connection structures as known in the art. Generally, adirect connection is desired between the cap 16 and the endplate 20, sothat the cover 12 is retained by such connection, but where the specificnature of the connection is not meant to be limiting.

With the direct connection between the cap 16 and the endplate 20, thecover 12 can be easier and more cost effective to produce. In previousfuel filters, the cap was connected directly to the shell or cover (e.g.by threaded engagement) and typically employed a coil spring to helpmaintain the filter element (e.g. cartridge) in position. The fluidfilters described herein, however, eliminate the thread on the cover orhousing and can eliminate the need for a spring. Such a spring-lessconfiguration can provide for a more generically produced cover withadded freedom as to the materials that may be employed to produce it. Asthe spring can be eliminated, problems associated with spring failure orspring pressure overcoming the assembly connection can also be avoided.Other benefits can include an overall height reduction of the fluidfilter, since a spring is no longer needed which previously increasedfilter height. Further, as the direct connection of the endplate withthe cap retains the cover, easier servicing can be achieved because thecap, filter element, and cover can be removed together without firstremoving the cover from the filter element.

It will be appreciated, however, that the fluid filter designs describedherein (including fluid filter 10) can be used in retrofit applicationsof existing fluid filters. As one example of a retrofit application, theendplate and cap design described herein can be used with other fuelfilters such as those produced by DAVCO Technology, LLC. For example,the threaded portion of the endplate 20 can be constructed to mate withthreaded configurations of existing caps. Additionally, the endplate 20can have its connection structure 30 be constructed so that the raisedboss structure has a recessed surface 36 that can act as a spring pocketwhen a spring is used. The raised boss of the connection structure 30and the recessed surface 36 can allow for a spring to be disposedbetween the cap 16 and the endplate 20, while having enough clearance sothat the spring does not interfere with the attachment of the cap 16 andthe endplate 20. For example, the diameter considerations of therecessed surface 36 and boss structure can be modified accordingly so asto provide retrofit capability.

As described above, the endplate 20 in some embodiments is configuredand arranged to control which filter element can be used in the fluidfilter assembly. In one example, the connection structure 30 isconfigured to indicate a micron rating of the filter element. When athreaded engagement is employed, for example, the threaded portion onthe endplate 20 can have a certain thread configuration that correspondsto a certain micron rating. For instance, more or less threads and thespacing of the threads can be modified to correspond to various micronratings (e.g. ranging from 3 to 50 microns). That is, the micron ratingof the media of the filter element can be dependant upon and correspondto the thread structure used for the endplate. For example, low micronrated filter elements may have less threads and higher micron ratedelements can have more threads. In such a configuration, the connectionstructure 30 (e.g. threaded portion) can help ensure that the filterelement 11 with the correct micron rating is installed. That is, if thecorrect micron rated filter element is not selected, then it will notmate to the cap 16.

The endplate 20 can include other structures, such as the slots and tabsdescribed below, which can help with indicating the micron rating of thefilter element 11, and also help with alignment and maintaining theposition of the filter element 11. While FIGS. 1-8 show these featurestogether in the filter element 11, they are not necessarily required incombination as the filter element 11 can include any one of thesestructures alone or in combination with the threaded engagement featuredescribed above.

As further shown in FIGS. 1-8, the endplate 20 in some embodiments caninclude at least one slot 34 on its outer surface. In one example, anouter side wall of the connection structure 30 (e.g. raised boss) canform part of the slot 34. Additional sidewalls 32 form the remainingspace of the slot 34, where the sidewalls 32 extend outward from theouter surface of the connection structure 30 and along the main surfaceof the endplate 20. The slot 34 is receivable of a protrusion 15 thatextends from an inner surface of the cover 12 (best shown in FIGS. 6-8).The protrusion 15 can resemble a wedge-like structure that plugs or canotherwise be inserted into the space created by the slot 34.

With further reference to the sidewalls 32, the sidewalls also extendgenerally upward from the main surface of the endplate 20. As shown, thesidewalls 32 are generally perpendicular to the main surface of theendplate 20. It will be appreciated, however, that the sidewalls 32 canextend from the main surface of the endplate 20 at different angles. Asone example, the sidewalls 32 can provide a self-ramping feature suchthat they are come closer together or taper toward each other at themain surface of the endplate. Likewise, the protrusion 15 can taper soas to match the same shape taken by the slot 34. Such a configurationcan allow for easier locating and installment of the cover 12 over thefilter element 11.

As shown, a plurality of slots 34 and protrusions 15 may be used. Itwill be appreciated that the number of slots 34 and protrusions 15 isnot meant to be limiting as more or less slots 34 and protrusions 15 maybe employed than what is shown in the Figs.

When the slot 34 and protrusion 15 are engaged, their relationship canbe configured such that the filter element 11 and the cover 12 areretained to each other. As some non-limiting examples, the slot 34 andprotrusion 15 can have an interference fit or a snap fit configurationwhen they are engaged. It will be appreciated that the protrusion 15 canbe released from engagement with the slot 34, such as when a sufficientamount of force is used to remove the cover 12 from the endplate 20 ifsuch disassembly is desired.

In some embodiments, the slot(s) 34 are configured and arranged tocontrol which filter element can be used in the fluid filter assembly.In one example, the slot(s) 34 can correspond to a micron rating of thefilter element 11. By way of example, the endplate 20 can have slots 34of a certain size and/or shape, and/or a certain number of slots 34 andspacing, which can be used to show correspondence to a certain micronrating. That is, the micron rating of the media 14 of the filter element11 is dependant upon and corresponds to the slot 34 structure. Forexample, low micron rated filter elements may have less or smaller slotsand higher micron rated elements can have more or larger slots. In sucha configuration, the slots 34 can help ensure that the filter element 11with the correct micron rating is installed. That is, if the correctmicron rated filter element is not selected, then it will not engagewith the cover 12.

In another embodiment, a plurality of tabs 35 can be disposed about aperimeter of the endplate 20. As shown, the tabs 35 extend outward fromthe perimeter of the endplate 20. The tabs 35 can resemble bump-likestructures protruding from the endplate 20. As shown in FIG. 2, forexample, the tabs 35 can contact the inner sidewall of the cover 12. Thearrangement of the tabs 35 can help align the filter element 11 withinthe cover 12. In some embodiments, the tabs 35 can engage the innersidewall of the cover 12 in an interference fit, but also be releasableif enough force is applied to remove the contact. Other configurationscan include, but are not limited to the cover 12 having grooves (notshown) along the inner sidewall, such that the tabs 35 slide within thegrooves when the filter element 11 is placed inside the cover 12. Ifgrooves are employed, the tabs 35 can be releasably engaged with thegrooves to remove the filter element 11 from the cover 12 if suchdisassembly is desired. It will be appreciated that such grooves easilycan be formed or machined into the inner sidewall of the cover 12 aschannels that are slightly larger than the dimension of the tabs 35,such that the tabs 35 can slide along when the filter element 11 isinserted into the cover 12. Some examples of the engagement structurebetween the tab 35 and grooves may be, but is not limited to, arelatively loose engagement or an interference fit.

In some embodiments, the tabs 35 are configured and arranged to controlwhich filter element can be used in the fluid filter assembly. In oneexample, the tabs 35 can correspond to a micron rating of the filterelement 11. By way of example, the endplate 20 can have tabs 35 of acertain size and/or shape, and/or a certain number of tabs 35 andspacing, which can be used to show correspondence to a certain micronrating. That is, the micron rating of the media 14 is dependent upon andcorresponds to the tab 35 structure. For example, low micron ratedfilter elements may have less or smaller tabs and higher micron ratedelements can have more or larger tabs. In such a configuration, the tabs35 can help ensure that the filter element 11 with the correct micronrating is installed. That is, if the correct micron rated filter elementis not selected, then it cannot be used with the cover 12.

With reference to endplate 22, the endplate 22 includes the flow passage52. The endplate 22 can be connected to a filtration system (e.g. fuelfiltration). The flow passage 52 allows for exit of ‘clean’ filteredfluid from the fluid filter 10 or allows for entry of fluid to befiltered depending on the direction of fluid flow. The filter element 11is disposed within the cover 12, such that that endplate 22 is proximatethe generally open side or end of the cover. Such a configuration issometimes desired since this area of the cover is the inlet/outlet sidewhere filtered fluid and fluid to be filtered respectively exit andenter the fluid filter 10. In some embodiments, a gasket seal 50 isdisposed within the flow passage 52. The gasket seal 50 can resemble agrommet-like structure that plugs into the flow passage 52. The gasketseal 50 helps to seal the fluid filter 10 when it is connected toremaining equipment of a filtration system and helps separate filteredfluid from fluid to be filtered.

As further shown in FIG. 2, for example, the filter element 11 caninclude a center tube 60 having a flow passage 62 therethrough in fluidcommunication with the open flow passage 52 (see e.g. FIG. 10) ofendplate 22. As shown, the center tube 60 is connected to both endplates20, 22, where the media 14 is disposed around the center tube 60 in acylindrical arrangement, and where the center tube 62 includes apertures64 that allow the working fluid to flow into and out of the flow passage62 of the center tube 60. Center tubes in such fluid filters arewell-known and need not be further described. It also will beappreciated that a center tube may not be employed at all and the centerarea inside the filter element 11 can be the flow passage in fluidcommunication with flow passage 52.

As above, the inventive concepts for an improved filter design aredescribed with respect to a fuel filter for illustration purposes only.It wilt be appreciated, however, that the disclosure is not meant to belimiting to fuel filters, and that the inventive concepts describedherein can be used in and suitably adapted for other fluid filterassemblies, such as by-pass and lube filtration technologies. It will befurther appreciated that various working fluids in need of filtration,including but not limited to fuel, can benefit from the inventiveconcepts disclosed herein.

FIGS. 9-11 show another example of a fluid filter 100 with an improvedattachment interface. As with fluid filter 10, the fluid filter 100 isan assembly including a cover 102, a filter element 111 (best shown inFIG. 10), and a cap 106. A difference between fluid filter 10 and fluidfilter 100 is that fluid filter 100 does not show outer tabs on theendplate (e.g. tabs 35 in FIGS. 1-8).

As with filter element 11, the filter element 111 resembles acartridge-like structure having a filtering media 104 disposed betweentwo endplates 120, 122. Generally, the media 104 allows a working fluidto be filtered therethrough. It will be appreciated that material forfiltration media and their constructions are well known. It further willbe appreciated that the filtering media 104 can have various micronratings to achieve a desired filtration capability for removingundesired contaminants of various sizes from the working fluid. As someexamples only, the filtering media 104 can be constructed of material soas to give the filtering media a micron rating in the range of 3 to 50microns. Installing the proper micron rated filter element into a fluidfilter is important for maintaining efficient filtration in a givenfiltration system and for protecting operating equipment, such as anengine.

In one embodiment, endplate 122 is a bottom endplate and includes anopen flow passage 152 (best shown in FIG. 10) that allows a workingfluid to flow into or out of the filtering media 104 during operation.The flow passage 152 is for connecting the fluid filter 100 to otherequipment of a filtration system. In one embodiment, endplate 120 is atop endplate. It will be appreciated that either endplate 120, 122 maybe configured to have the flow passage 152, and that the reference totop and bottom is for illustration purposes. The orientation of thefilter element 111 with respect to its positioning in the cover 102 isdependent upon which of the endplates 120, 122 has the flow-passage 152.

In some examples, the endplate that does not have the flow passage (e.g.endplate 120) is a closed structure. That is, the endplate 120 does nothave any openings and closes off one end of the filter media 104. Inother examples, the endplate 120 can have a valve 108 disposed at anopening thereof. When such a valve 108 is employed, it can close overtime during operation, for example when the filter element 111 needs tobe replaced, such as when the fluid filter 100 is filled with ‘dirty’fluid during its particular filtration application (e.g. fuelfiltration). As one example, the valve 108 is a check valve or crackingpressure valve as generally known by one of skill in the art. In FIG. 2,the valve 108 is a one-way seated member or plunger-like structure thatcan close the opening in the endplate 120.

The cover 102 generally houses the filter element 111. The cover 102 hasan opening that is in fluid communication with the flow passage 152 ofthe endplate 122. As shown in FIG. 1, the cover 102 also may be a clearor generally transparent cover that one can see through. The cover 102is generally open on a side or end that is in fluid communication withthe flow passage 152 (see bottom of fluid filter 100). The cover 102also includes an opening 113 proximate the endplate 120. As shown, thecover 102 has wall surfaces that surround the opening 113. These wallsurfaces are retained between the connection of the cap 106 to theendplate 120 when the fluid filter 100 is assembled (further describedbelow).

The cap 106 closes the opening 113 of the cover 102. A seal 142 can bedisposed about the opening 113 or on the cap 106. In one embodiment, theseal 142 is an o-ring. In the closed position, the cap 106 is directlyconnected to the endplate 120.

The endplate 120 includes a connection structure 130. The cap 106 isconnected to the connection structure 130 of the endplate 120, such thatthe cover 102 is retained between the cap 106 and the endplate 120 (seee.g. FIG. 2).

In one embodiment, the connection structure 130 of the endplate includesa threaded arrangement. As shown, the connection structure 130 is athreaded portion that can be threadedly engaged with a threaded portion140 on the cap 106. As one example, the connection structure 130 isconstructed as a raised boss structure extending from a main surface ofthe endplate 120 and having a female threaded portion, and the cap 106is constructed as a male threaded portion.

It will be appreciated that other threaded arrangements may be employed,for example, the endplate 120 may have the male thread and the cap mayhave the female thread. It further will be appreciated that theconnection structure 130 of the endplate 120 is not meant to be limitingto a threaded arrangement. Other examples that can be used include butare not limited to a snap fit, an interference fit, or a quarter turnlock, or other connection structures as known in the art. Generally, adirect connection is desired between the can 106 and the endplate 120,so that the cover 102 is retained by such connection, but where thespecific nature of the connection is not meant to be limiting.

With the direct connection between the cap 106 and the endplate 120, thecover 102 can be easier and more cost effective to produce. In previousfuel filters, the cap was connected directly to the shell or cover (e.g.by threaded engagement) and typically employed a coil spring to helpmaintain the filter element (e.g. cartridge) in position. The fluidfilters described herein, however, eliminate the thread on the cover orhousing and can eliminate the need for a spring. Such a spring-lessconfiguration can provide for a more generically produced cover withadded freedom as to the materials that may be employed to produce it. Asthe spring can be eliminated, problems associated with spring failure orspring pressure overcoming the assembly connection can also be avoided.Other benefits can include an overall height reduction of the fluidfilter, since a spring is no longer needed which previously increasedfilter height. Further, as the direct connection of the endplate withthe cap retains the cover, easier servicing can be achieved because thecap, filter element, and cover can be removed together without firstremoving the cover from the filter element.

As with fluid filter 10 above, it will be appreciated that the fluidfilter 100 can be used in retrofit applications of existing fluidfilters. As one example of a retrofit application, the endplate and capdesign described herein can be used with other fuel filters such asthose produced by DAVCO Technology, LLC. For example, the threadedportion of the endplate 120 can be constructed to mate with threadedconfigurations of existing caps. Additionally, the endplate 120 can haveits connection structure 130 be constructed so that the raised bossstructure has a recessed surface 136 that can act as a spring pocketwhen a spring is used. The raised boss of the connection structure 130and the recessed surface 136 can allow for a spring to be disposedbetween the cap 106 and the endplate 120, while having enough clearanceso that the spring does not interfere with the attachment of the cap 106and the endplate 120. For example, the diameter considerations of therecessed surface 136 and boss structure can be modified accordingly soas to provide retrofit capability.

As described above, the endplate 120 in some embodiments is configuredand arranged to control which filter element can be used in the fluidfilter assembly. In one example, the connection structure 130 isconfigured to indicate a micron rating of the filter element. When athreaded engagement is employed, for example, the threaded portion onthe endplate 120 can have a certain thread that corresponds to a certainmicron rating. For instance, more or less threads and the spacing of thethreads can be modified to correspond to various micron ratings (e.g.ranging from 3 to 50 microns). That is, the micron rating of the mediaof the filter element can be dependant upon and correspond to the threadstructure used for the endplate. In such a configuration, the connectionstructure 130 (e.g. threaded portion) can help ensure that the filterelement 111 with the correct micron rating is installed. That is, if thecorrect micron rated filter element is not selected, then it will notmate to the cap 106.

The endplate 120 can include other structures, such as the slotsdescribed below, which can help with indicating the micron rating of thefilter element 111 and also help with alignment and maintaining theposition of the endplate 120. While FIGS. 9-11 show these featurestogether in the filter element 111, they are not necessarily required incombination as the filter element 11 can include any one of thesestructures alone or in combination with the threaded engagement featuredescribed above.

As shown in FIGS. 9-11, the endplate 120 in some embodiments can includeat least one slot 134 on its outer surface. In one example, an outerside wall of the connection structure 130 (e.g. raised boss) can formpart of the slot 134. Additional sidewalls 132 form the remaining spaceof the slot 134, where the sidewalls 132 extend outward from the outersurface of the connection structure 130 and along the main surface ofthe endplate 120. The slot 134 is receivable of a protrusion 115 thatextends from an inner surface of the cover 102 (best shown in FIG. 9).The protrusion 115 can resemble wedge-like structure that can plug orotherwise be inserted into the space created by the slot 134.

With further reference to the sidewalls 132, the sidewalls also extendgenerally upward from the main surface of the endplate 120. Thesidewalls 132 are generally perpendicular to the main surface of theendplate 120, and taper toward the perimeter of the endplate 120. Aswith the sidewalls 32 of endplate 20, sidewalls 132 can extend from themain surface of the endplate at different angles. For example, thesidewalls 132 can be ramped such that they are come closer together ortaper toward each other at the main surface of the endplate. Likewise,the protrusion 115 can taper so as to match the same shape taken by theslot 134. Such a configuration can allow for easier locating andinstallment of the cover 102 over the filter element 111.

As with filter element 111, a plurality of slots 134 and protrusions 115may be used (only one protrusion 115 shown for purposes ofillustration). It will be appreciated that the number of slots 134 andplugs 115 is not meant to be limiting.

When the slot 134 and protrusion 115 are engaged, their relationship canbe configured such that the filter element 111 and the cover 102 areretained to each other. As some non-limiting examples, the slot 134 andprotrusion 115 can have an interference fit or a snap fit configurationwhen they are engaged. It will be appreciated that the protrusion 115can be released from engagement with the slot 134, such as when asufficient amount of force is used to remove the cover 102 from theendplate 120 if such disassembly is desired.

In some embodiments, the slot(s) 134 are configured and arranged tocontrol which filter element can be used in the fluid filter assembly.In one example, the slot(s) 134 can correspond to a micron rating of thefilter element 111. By way of example, the endplate 120 can have slots134 of a certain size and/or shape, and/or a certain number of slots 134and spacing, which can be used to show correspondence to a certainmicron rating. That is, the micron rating of the media 104 of the filterelement 111 is dependant upon and corresponds to the slot 134 structure(e.g. as in fluid filter 10). In such a configuration, the slots 134 canhelp ensure that the filter element 111 with the correct micron ratingis installed. If the correct micron rated filter element is notselected, then it will not engage with the cover 120.

Differently from fluid filter 10, fluid filter 100 does not show tabs(e.g. tabs 35) at the perimeter of the endplate 120. It will beappreciated, however, that a plurality of tabs can be disposed about aperimeter of the endplate 120 as similarly described with respect to thefluid filter 100. Also, such a tab structure if employed can beconfigured and arranged so as to control which filter element can beused in the fluid filter assembly. That is, tabs can be employed tocorrespond to a micron rating of the filter element 111.

With reference to endplate 122, the endplate 122 includes the flowpassage 152. The endplate 122 can be connected to a filtration system(e.g. fuel filtration). The flow passage 152 allows for exit of ‘clean’filtered fluid from the fluid filter 100 or allows for entry of fluid tobe filtered depending on the direction of fluid flow. The filter element111 is disposed within the cover 102, such that that endplate 122 isproximate the generally open side or end of the cover. Such aconfiguration is sometimes desired since this area of the cover is theinlet/outlet side where filtered fluid and fluid to be filteredrespectively exit and enter the fluid filter 100. In some embodiments, agasket seal 150 is disposed within the flow passage 152. The gasket seal150 can resemble a grommet-like structure that plugs into the flowpassage 152. The gasket seal 150 helps to seal the fluid filter 100 whenit is connected to remaining equipment of a filtration system and helpsseparate filtered fluid from fluid to be filtered.

As further shown in FIG. 10, for example, the filter element 111 caninclude a center tube 160 having a flow passage 162 therethrough influid communication with the open flow passage 152 of endplate 122. Asshown, the center tube 160 is connected to both endplates 120, 122,where the media 104 is disposed around the center tube 160 in acylindrical arrangement, and where the center tube 160 includesapertures 164 that allow the working fluid to flow into and out of theflow passage of the center tube 160. Center tubes in such fluid filtersare well-known and need not be further described. It also will beappreciated that a center tube may not be employed at all and the centerarea inside the filter element 111 can be the flow passage in fluidcommunication with flow passage 152.

As one example of the flow direction within the fluid filter 100 duringoperation, a working fluid first enters the fluid filter 100 through thegenerally open side of the cover 102 and around the endplate 122. Theworking fluid then flows through the filtering media 104, through theapertures 164, and into the flow passage 162 of the center tube 160. Theworking fluid exits the flow passage 152 of the endplate 122 afterflowing through the flow passage 162 of the center tube 160. (See arrowsof FIG. 10.) Fluid filter 10 can also have a similar flow direction (seee.g. FIG. 2). It will be appreciated that the flow direction may bereversed for either of the fluid filters 10, 100 where a working fluidto be filtered first enters the open flow passage 52, 152, flows throughthe flow passage 62, 162 and apertures 64, 164 of the center tube 60,160, and then exits the cover.

As described, the improved attachment interface and its variousconfigurations can help provide a keying function for a fluid filter toensure that the filter element with the correct micron rating is beingused. In the example of fuel filtration systems, installation andservicing of a filter element having the correct micron rating isimportant for maintaining efficient filtration in a given filtrationsystem and for protecting equipment, such as an engine. The attachmentinterfaces and its features provide inventive concepts that can alsohelp secure aftermarket, where the assembly structure is uniquelyconfigured to prevent others from copying. Retrofitting capability ofthe endplate and cap structures described herein also is available withexisting fluid filters.

While the above is a complete description of the preferred embodimentsof the invention, various alternatives, modifications, and equivalentsmay be used. Therefore, the above description should not be taken aslimiting the scope of the invention which is defined by the appendedclaims.

What is claimed is:
 1. A fluid filter comprising: a filter elementhaving a media disposed between two endplates, the media allows aworking fluid to be filtered through the media, one of the two endplatesincludes an opening that allows the working fluid to flow into or out ofthe filter media during operation, the other of the two endplatesincludes a connection structure; a flow passage to filter the workingfluid, the flow passage being through the media and the endplate withthe opening; a cover that houses the filter element, the cover having anopening in fluid communication with the opening of the one endplate andhaving a fill opening proximate the other of the two endplates; and acap that closes the cover at the opening proximate the other of the twoendplates, the cap has a connection structure to connect to theconnection structure of the other of the two endplates, wherein thecover includes wall surfaces, the wall surfaces being retained betweenthe cap and the other of the two endplates and by connection of theconnection structures of the cap and the other of the two endplates, andwherein the other of the two endplates having the connection structureis a structure with no flow passage for the working fluid duringoperation, wherein the other of the two endplates having the connectionstructure includes a check valve that closes over time during operationuntil the media needs to be replaced, and wherein the working fluid doesnot flow through the check valve during operation.
 2. The fluid filterof claim 1, wherein the connection structure is configured to correspondto a micron rating of the filter element.
 3. The fluid filter of claim1, wherein the connection structure of the other of the two endplates isa threaded arrangement, where the cap threadedly engages the other ofthe two endplates.
 4. The fluid filter of claim 1, further comprising atleast one slot on an outer surface of the other of the two endplates andfurther comprising at least one protrusion extending from an innersurface of the cover, the at least one protrusion is insertable into aspace defined by the at least one slot.
 5. The fluid filter of claim 4,wherein the at least one slot and the at least one protrusion areconnected so that the filter element and the cover are retained to eachother.
 6. The fluid filter of claim 4, wherein the at least one slot andthe at least one protrusion are releasably engaged.
 7. The fluid filterof claim 4, wherein the at least one slot is configured to correspond toa micron rating of the filter element.
 8. The fluid filter of claim 1,further comprising a plurality of tabs disposed about a perimeter of theother of the two endplates, the tabs extending outward from theperimeter.
 9. The fluid filter of claim 8, wherein the tabs areconfigured to correspond to a micron rating of the filter element.
 10. Afilter element for a fluid filter device comprising: a top endplate anda bottom endplate; a media disposed between the top and bottomendplates, the media allows a working fluid to be filtered through themedia, a flow passage to filter the working fluid, the flow passagebeing though the media and the bottom endplate; the top endplate thatduring filling of the fluid filter device directs fluid to the flowpassage, the top endplate includes a connection structure adapted fordirect and removeable connection to a cap that can be opened and closedfor filling or servicing the fluid filter device, and adapted to retainwall surfaces of a cover of the fluid filter device between the topendplate and the cap, the bottom endplate includes an opening thatallows the working fluid to flow through the flow passage into or out ofthe filter media during use of the filter element, wherein the topendplate is a structure with no flow passage for the working fluidduring operation, wherein the top endplate includes a check valve thatcloses over time during operation until the media needs to be replaced,and wherein the working fluid does not flow through the check valveduring operation.
 11. The filter element of claim 10, wherein theconnection structure is a threaded arrangement.
 12. The filter elementof claim 10, further comprising at least one slot on an outer surface ofthe top endplate.
 13. The filter element of claim 12, wherein the atleast one slot is configured to correspond to a micron rating of themedia.
 14. The filter element of claim 10, further comprising aplurality of tabs disposed about a perimeter of the top endplate, thetabs extending outward from the perimeter.
 15. The filter element ofclaim 14, wherein the tabs are configured to correspond to a micronrating of the media.
 16. The filter element of claim 10, wherein the topendplate is a closed structure.